PURPOSE: To assess the potential of αvβ6-integrin as a theranostic target in esophageal cancer. METHODS: Membranous β6-integrin (ITGB6) expression was analyzed in 306 specimens of human esophageal squamous cell carcinoma (ESCC) obtained by immunohistochemistry (IHC) from 100 patient cases (1, 37, 58, and 4 of grade G1, G2, G3, and G4, respectively). Ga-68 labeling of D0103 was done manually for preclinical experiments and fully automated for clinical application. Preclinical characterization of Ga-68-D0103 was performed in SCID mice bearing subcutaneous xenografts of H2009 (αvβ6-positive) or MDA-MB-231 (αvβ6-negative) carcinoma cell lines, by ex vivo biodistribution (10, 30, 90, and 180 min p.i) and PET imaging (30, 90, and 180 min p.i.)., without and with co-injection of gelofusine (4% succinylated gelatin). A patient with type-II diabetes (f, 68y, 115 kg) with proximal G2 ESCC was investigated by Ga-68-D0103 PET/CT (193 MBq) at 15, 45, 90, and 104 min p.i.. RESULTS: 99% of ESCC cases were found β6-integrin positive by IHC, of which 48%, 31%, and 20% showed strong, moderate, and low ITGB6 expression, respectively, with no correlation to tumor grade. Ex vivo biodistribution of Ga-68-D0103 in H2009 xenografted mice after 30, 90, and 180 min showed tumor-to-blood ratios of 6.8, 37, and 124, respectively; tumor-to-muscle ratios of 12, 14, and 36, respectively; tumor-to-liver ratios of 10, 17, and 14, respectively; and tumor-to-pancreas ratios of 20, 47, and 56, respectively. Co-administration of gelofusine did not change the tumor uptake but reduced the kidney uptake by 89% (from 178%iA/g to 19.1%iA/g, 90 min p.i.), resulting in an 8.7-fold higher tumor/kidney ratio. µPET imaging in H2009 xenografted mice confirmed a high tumor uptake and low background already 30 min p.i.. Blockade biodistribution and µPET in αvβ6-(-) MDA-MB-231 mice demonstrated target specificity. Clinical PET/CT of a patient with ESCC showed increasing tracer uptake over time in the primary tumor (SUVmax 9.0 and 11.3 at 15 and 104 min p.i., respectively) and in a lymph node metastasis (SUVmax 19.5 and 28.3, respectively), and a decreasing blood pool activity (SUVmean 2.75 and 0.98, respectively). CONCLUSIONS: High (99%) membranous expression frequency and density on tumor cells underscores the potential of αvβ6-integrin as a theranostic target in ESCC, suggesting that αvβ6-integrin PET/CT imaging may adopt a role in re-staging and therapy guidance in this cancer type. The prolonged tumor retention furthermore indicates a therapeutic potential of αvβ6-integrin targeted radiopharmaceuticals when labeled with radionuclides such as lutetium-177, terbium-161, or actinium-225.

• Klíčová slova
• Esophageal Cancer, Integrins, Positron Emission Tomography, Surveillance, Theranostics,
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Severe combined immunodeficiency (SCID) is a fatal but treatable inborn error of immunity (IEI). Newborn screening (NBS) using T-cell receptor excision circles (TREC) has been adopted globally, with very few countries incorporating kappa recombination excision circles (KREC) to also detect early B-cell development disorders, such as X-linked agammaglobulinemia (XLA). OBJECTIVE: To evaluate the effectiveness of a 2-year pilot SCID NBS program in the Czech Republic, emphasising the utility of combined TREC/KREC screening. METHODS: Between January 2022 and December 2023, a dual TREC/KREC NBS pilot was conducted across the Czech Republic, alongside spinal muscular atrophy (SMA) screening. Approximately 200,000 newborns were screened using quantitative real-time PCR on dried blood spots collected 48-72 h after birth. RESULTS: The pilot referred 58 newborns, identifying 21 cases of IEI, including two SCID cases, with an overall incidence of TREC/KREC screenable IEI of 10.5/100,000 newborns. SCID incidence was 1/100,000. KREC screening proved invaluable, detecting 10 cases of congenital agammaglobulinemia including novel non-XLA forms, which increased the estimated incidence of agammaglobulinemia in the Czech Republic sixfold. Over one-third of low KREC results were linked to maternal immunosuppression. CONCLUSION: The Czech pilot demonstrated the effectiveness of integrated TREC/KREC NBS in detecting both T- and B-cell immunodeficiencies. As of 2024, SCID and SMA screening are included in the nationwide NBS, with KREC screening significantly improving early detection of B-cell disorders.

• Klíčová slova
• IGLL1, KREC, SCID, TREC, XLA, agammaglobulinemia, dried blood spot, screening, severe combined immunodeficiency,
• MeSH
• agamaglobulinemie diagnóza   MeSH
• B-lymfocyty imunologie   MeSH
• lidé MeSH
• novorozenec MeSH
• novorozenecký screening * metody   MeSH
• pilotní projekty MeSH
• receptory antigenů T-buněk * genetika   MeSH
• těžká kombinovaná imunodeficience * diagnóza   genetika   epidemiologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• receptory antigenů T-buněk * MeSH

Persistent selective T-lymphocytopenia is found both in SCID and congenital athymia. Without molecular diagnosis, it is challenging to determine whether HCT or thymus transplantation ought to be performed. Ex vivo T-lymphopoiesis assays have been proposed to assist clinical decision-making for genetically undefined patients. We investigated 20 T-lymphocytopenic patients, including 13 patients awaiting first-line treatment and 7 patients with failed immune reconstitution after previous HCT or thymus transplantation. Whilst developmental blocks in ex vivo T-lymphopoiesis indicated hematopoietic cell-intrinsic defects, successful T-lymphocyte differentiation required careful interpretation, in conjunction with clinical status, immunophenotyping, and genetic investigations. Of the 20 patients, 13 proceeded to treatment, with successful immune reconstitution observed in 4 of the 6 patients post-HCT and 4 of the 7 patients after thymus transplantation, the latter including two patients who had previously undergone HCT. Whilst further validation and standardization are required, we conclude that assessing ex vivo T-lymphopoiesis during the diagnostic pathway for genetically undefined T-lymphocytopenia improves patient outcomes by facilitating corrective treatment choice.

• Klíčová slova
• Artificial thymic organoids (ATO), Congenital athymia, Diagnostic assays, Ex vivo T-lymphocyte differentiation, Hematopoietic cell transplantation (HCT), Newborn screening, Severe combined immunodeficiency (SCID), T-lymphocytopenia, Thymus transplantation,
• MeSH
• dítě MeSH
• imunofenotypizace MeSH
• kojenec MeSH
• lidé MeSH
• lymfopenie * terapie   imunologie   genetika   diagnóza   MeSH
• lymfopoéza * imunologie   MeSH
• předškolní dítě MeSH
• T-lymfocyty * imunologie   MeSH
• těžká kombinovaná imunodeficience imunologie   terapie   genetika   MeSH
• thymus transplantace   MeSH
• transplantace hematopoetických kmenových buněk MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Patient-derived xenografts (PDXs) can be improved by implantation of a humanized niche. Nevertheless, the overall complexity of the current protocols, as well as the use of specific biomaterials and procedures, limits the wider adoption of this approach. Here, we identify the essential minimum steps required to create the humanized scaffolds and achieve successful acute myeloid leukemia (AML) engraftment. We compared seven biomaterials, which included both published and custom-designed materials. The highest level of bone marrow niche was achieved with extracellular matrix gels and custom collagen fiber, both of which allowed for a simple non-surgical implantation. The biomaterial selection did not influence the following AML infiltration. Regarding xenotransplantation, standard intravenous administration produced the most robust engraftment, even for two out of four otherwise non-engrafting AML samples. In contrast, direct intra-scaffold xenotransplantation did not offer any advantage. In summary, we demonstrate that the combination of an injectable biomaterial for scaffold creation plus an intravenous route for AML xenotransplantation provide the most convenient and robust approach to produce AML PDX using a humanized niche.

• Klíčová slova
• AML, T‐cell, collagen, mouse model, ossicles, patient‐derived xenografts,
• MeSH
• akutní myeloidní leukemie * patologie   MeSH
• biokompatibilní materiály * farmakologie   aplikace a dávkování   MeSH
• heterografty MeSH
• lidé MeSH
• myši SCID MeSH
• myši MeSH
• tkáňové podpůrné struktury * chemie   MeSH
• transplantace heterologní * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biokompatibilní materiály * MeSH

BACKGROUND: Overexpression of human epidermal growth factor receptor type 2 (HER2) occurs in multiple carcinomas. For example, up to 20% of breast cancer cases are classified as HER2 positive (HER2+). Treatment of this condition typically involves immunotherapy using monoclonal antibodies, such as trastuzumab or pertuzumab. The precise targeting of monoclonal antibodies to HER2+ tumour lesions can be used as well in radioimmunotherapy to deliver medical radionuclides exactly to the afflicted area and therefore minimize radiation exposure of healthy tissues. In this study, DOTA conjugates of monoclonal antibodies trastuzumab and pertuzumab were prepared and tested in vitro. One of these, 225Ac-DOTA-pertuzumab, was also the subject of an ex vivo biodistribution study with normal as well as HER2+ and HER2- tumour-xenografted mice. This radioconjugate has not been previously described. RESULTS: Three DOTA-conjugates of HER2 targeting monoclonal antibodies, one of trastuzumab and two of pertuzumab, were prepared and radiolabelled with 225Ac in different molar ratios. This procedure led to an optimisation of the preparation and radiolabelling process. The radioconjugates were shown to be highly stable in vitro in both fetal bovine serum and phosphate buffered saline under room temperature and decreased temperature for 10 days. In vitro cell studies with HER2-overexpressing cell-line (SKOV-3) and low HER2-expressing cell line (MDA-MB-231) proved that radioconjugates of both antibodies have high binding specificity and affinity towards HER2 receptors. These findings were confirmed for a novel radioconjugate 225Ac-DOTA-pertuzumab in an ex vivo biodistribution study, where uptake in HER2+ tumour was 50 ± 14% ID/g and HER2- tumour showed uptake comparable with healthy tissues (max. 5.0 ± 1.7% ID/g). The high uptake observed in the spleen can be attributed to the elimination of the antibody, as well as the use of an immunedeficient mouse strain (SCID). CONCLUSIONS: During this study, the optimization of preparation and radiolabelling of HER2 targeting antibodies with 225Ac was accomplished. Furthermore, the radioconjugate 225Ac-DOTA-pertuzumab was prepared and evaluated for the first time. The radioconjugates of both tested antibodies demonstrated excellent qualities in terms of stability and HER2 receptor affinity. Initial ex vivo studies indicated that especially the radioconjugate 225Ac-DOTA-pertuzumab is a very promising candidate for further more detailed in vivo studies.

• Klíčová slova
• Actinium-225, HER2, MDA-MB-231, Pertuzumab, SKOV-3, Targeted alpha therapy, Trastuzumab,
• Publikační typ
• časopisecké články MeSH

Initiation of newborn screening (NBS) programs in Europe dates back to the 1960s. One of the most recent expansions of NBS programs was the addition of severe combined immunodeficiency (SCID) based on detection of T-cell receptor excision circles (TRECs). In this review, we present an overview of the current situation in Europe. To avoid a biased overview based on only published results, a 37-item survey on TREC-based NBS was sent to representatives of 46 European countries. With a response rate of 83%, we collected data of 38 countries. Seventeen of the 38 European countries that have completed the survey have nationally or regionally implemented TREC-based NBS. The survey results emphasize similarities and differences as well as common practices and challenges in TREC-based NBS. Because TRECs are a general surrogate marker for severe T lymphocytopenia, conditions other than SCID are also identified. Therefore, the initial definition of the target disease as "SCID" might need to be reconsidered and extended to "SCID and severe T lymphocytopenia." Even though complete harmonization of TREC-based NBS programs across Europe will remain challenging, collaboration and close partnerships will help in the move toward universal TREC-based screening for all newborns, resulting in more infants with SCID and severe T lymphocytopenia being detected each year.

• Klíčová slova
• Europe, IEI, NBS, Newborn screening, SCID, TREC, inborn errors of immunity, severe T lymphocytopenia, severe combined immunodeficiency,
• MeSH
• lidé MeSH
• lymfopenie * diagnóza   epidemiologie   MeSH
• novorozenec MeSH
• novorozenecký screening * metody   MeSH
• receptory antigenů T-buněk genetika   MeSH
• T-lymfocyty * imunologie   MeSH
• těžká kombinovaná imunodeficience * diagnóza   epidemiologie   genetika   MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH
• Názvy látek
• receptory antigenů T-buněk MeSH

The therapeutic potential of targeting PI3K/AKT/PTEN signalling in B-cell malignancies remains attractive. Whilst PI3K-α/δ inhibitors demonstrate clinical benefit in certain B-cell lymphomas, PI3K signalling inhibitors have been inadequate in relapsed/refractory diffuse large B-cell lymphoma (DLBCL) in part, due to treatment related toxicities. Clinically, AKT inhibitors exhibit a differentiated tolerability profile offering an alternative approach for treating patients with B-cell malignancies. To explore how AKT inhibition complements other potential therapeutics in the treatment of DLBCL patients, an in vitro combination screen was conducted across a panel of DLCBL cell lines. The AKT inhibitor, capivasertib, in combination with the BCL-2 inhibitor, venetoclax, produced notable therapeutic benefit in preclinical models of DLBCL. Capivasertib and venetoclax rapidly induced caspase and PARP cleavage in GCB-DLBCL PTEN wildtype cell lines and those harbouring PTEN mutations or reduced PTEN protein, driving prolonged tumour growth inhibition in DLBCL cell line and patient derived xenograft lymphoma models. The addition of the rituximab further deepened the durability of capivasertib and venetoclax responses in a RCHOP refractory DLBCL in vivo models. These findings provide preclinical evidence for the rational treatment combination of AKT and BCL-2 inhibitors using capivasertib and venetoclax respectively alongside anti-CD20 antibody supplementation for treatment of patients with DLBCL.

• MeSH
• apoptóza účinky léků   MeSH
• bicyklické sloučeniny heterocyklické * farmakologie   terapeutické užití   MeSH
• difúzní velkobuněčný B-lymfom * farmakoterapie   patologie   MeSH
• fosfohydroláza PTEN metabolismus   MeSH
• lidé MeSH
• myši SCID MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• protokoly protinádorové kombinované chemoterapie * farmakologie   terapeutické užití   MeSH
• protoonkogenní proteiny c-akt * metabolismus   MeSH
• protoonkogenní proteiny c-bcl-2 * antagonisté a inhibitory   metabolismus   MeSH
• pyrimidiny * farmakologie   terapeutické užití   MeSH
• pyrroly farmakologie   terapeutické užití   MeSH
• rituximab farmakologie   terapeutické užití   MeSH
• sulfonamidy * farmakologie   terapeutické užití   MeSH
• xenogenní modely - testy protinádorové aktivity * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• BCL2 protein, human MeSH Prohlížeč
• bicyklické sloučeniny heterocyklické * MeSH
• capivasertib MeSH Prohlížeč
• fosfohydroláza PTEN MeSH
• protoonkogenní proteiny c-akt * MeSH
• protoonkogenní proteiny c-bcl-2 * MeSH
• pyrimidiny * MeSH
• pyrroly MeSH
• rituximab MeSH
• sulfonamidy * MeSH
• venetoclax MeSH Prohlížeč

• Klíčová slova
• Nijmegen breakage syndrome, granulomas, granulomatous lesions, hematopoietic stem cell transplantation, immunodeficiency,
• MeSH
• granulom etiologie   diagnóza   MeSH
• lidé MeSH
• syndrom Nijmegen breakage * genetika   MeSH
• těžká kombinovaná imunodeficience * terapie   komplikace   diagnóza   MeSH
• transplantace hematopoetických kmenových buněk * škodlivé účinky   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• kazuistiky MeSH

AIM: Circular DNA segments TREC (T-cell receptor excision circles) formed during T-lymphocyte maturation in the thymus, are a sensitive marker of thymic lymphocyte production in a broader manner. Quantification using qPCR is proposed as a surrogate marker of T cell malfunction in various primary and secondary conditions in a non-SCID selected risk newborn population. METHODS: We collected 207 dry blood spot samples during the years 2015-2018, from newly admitted risk newborns. TREC values calculated per 106 cells were determined and a cut-off values of 5th percentile was set. The positive control group consisted of patients (n=13) with genetically confirmed SCID. RESULTS: The median TREC value was 34,591.56 (18,074.08-60,228.58) for girls resp. 28,391.20 (13,835.01-51,835.93) per 106 cells for boys, P=0.046. Neonates born by C-section have been found to have higher TREC levels compared to neonates born by spontaneous delivery (P=0.018). In the group of preterm newborns (n=104), 3.8% had TREC value < 5th percentile, half of them died due to sepsis as opposed to no fatalities in preterm newborns with sepsis and TREC value > 5th percentile. In the group of term newborns (n=103) 9 children (8.7%) had TREC < 5th percentile, half of them were treated for asphyxia, with no fatal complications. CONCLUSION: TREC levels calculated for the 5th percentile of a risk neonatal group is suggested as a surrogate marker for increased risk of fatal septic complication. Early recognition of these newborns within a risk scoring system using TREC levels could lead to potentially lifesaving interventions.

• Klíčová slova
• SCID, TREC, immunodeficiency, newborn screening, risk neonates,
• MeSH
• intenzivní péče o novorozence MeSH
• kruhová DNA MeSH
• lidé MeSH
• lymfopenie MeSH
• novorozenec MeSH
• receptory antigenů T-buněk genetika   MeSH
• T-lymfocyty * imunologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kruhová DNA MeSH
• receptory antigenů T-buněk MeSH

Radiolabelled puromycin analogues will allow the quantification of protein synthesis through nuclear medicine-based imaging. A particularly useful application could be the non-invasive longitudinal visualisation of mycobacterial activity through direct quantification of puromycin binding. This study assesses the value of [68Ga]Ga-DOTA-puromycin in the visualisation of mycobacteria through positron emission tomography combined with magnetic resonance imaging (µPET/MRI). The radiopharmaceutical was produced by previously published and validated methods. [68Ga]Ga-DOTA-Puromycin imaging was performed on severe immunodeficient mice infected with Bacille Calmette-Guérin-derived M. Bovis (BCG). Acute and chronic infection stages were examined by µPET/MRI. A follow-up group of animals acted as controls (animals bearing S. aureus-derived infection and sterile inflammation) to assess tracer selectivity. [68Ga]Ga-DOTA-puromycin-µPET/MRI images revealed the acute, widespread infection within the right upper shoulder and armpit. Also, [68Ga]Ga-DOTA-puromycin signal sensitivity measured after a 12-week period was lower than that of [18F]FDG-PET in the same animals. A suitable correlation between normalised uptake values (NUV) and gold standard histopathological analysis confirms accurate tracer accumulation in viable bacteria. The radiopharmaceutical showed infection selectivity over inflammation but accumulated in both M. Bovis and S. Aureus, lacking pathogen specificity. Overall, [68Ga]Ga-DOTA-puromycin exhibits potential as a tool for non-invasive protein synthesis visualization, albeit without pathogen selectivity.

• Klíčová slova
• Fluorodeoxyglucose, Gallium-68, Molecular imaging, Mycobacterium tuberculosis, Positron emission tomography/magnetic resonance imaging,
• MeSH
• heterocyklické sloučeniny monocyklické chemie   MeSH
• magnetická rezonanční tomografie * metody   MeSH
• Mycobacterium bovis * MeSH
• mykobakteriózy diagnostické zobrazování   mikrobiologie   MeSH
• myši SCID MeSH
• myši MeSH
• organokovové sloučeniny MeSH
• pozitronová emisní tomografie * metody   MeSH
• radiofarmaka * chemie   MeSH
• radioizotopy galia * MeSH
• tuberkulóza diagnostické zobrazování   mikrobiologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• heterocyklické sloučeniny monocyklické MeSH
• organokovové sloučeniny MeSH
• radiofarmaka * MeSH
• radioizotopy galia * MeSH